The present invention relates generally to flashlights and more particularly to a flashlight with an adjustable light beam reflector.
Adjustable beam flashlights typically project a light beam that may be adjusted from a spot projected beam to a broad projected beam. The spot beam may be best produced by an axially symmetric concave parabolic reflector (or a modified paraboloid where the paraboloid is modified to project a spot beam of the intended pattern diameter) with the light source close to the focus of the paraboloid which produces generally collimated light rays resulting in a high intensity spot beam of light. The light beam may be broadened, as for example, in a conical shaped beam, by moving the light source further away from the focus of the paraboloid, preferably but not necessarily toward the larger end of the paraboloid, to produce a relatively nonparallel and diffuse radiating beam. A defocused spot beam, however, is not a good flood beam because the distribution of light is highly uneven. A spot beam is generally poorly suited for illuminating a nearby object because the intensity of the illumination is typically too great and the field of illumination is too narrow. Likewise, a flood beam is generally not suited for illuminating distant objects because the light beam is typically to diffuse to illuminate the distant object.